The importance of passive safety in vehicle rollover procedures is very great, since a large proportion of fatal single vehicle accidents may be attributed to a turnover. In the overall occurrence of accidents, the turnover of vehicles or rollover procedures at this time occupy a proportion of about 20 percent.
Against this background, new concepts for rollover sensing have been developed, which are able to detect, for instance, a vehicle turnover already at an early point in time. This assures that safety devices such as belt tensioners, head air bags and rollover bars are activated at the right time, and that the risk of injury is decreased.
Documents German Published Patent Application No. 100 19 416, German Published Patent Application No. 100 19 417 and German Published Patent Application No. 100 19 418 describe methods and devices based on evaluating one rotation rate sensor and two acceleration sensors, that are situated in the central air bag control device. The rotation rate sensor ascertains the speed of rotation about the longitudinal axis of the vehicle, according to the gyroscopic principle; the acceleration sensors additionally measure the vehicle's acceleration in the transversal axis and the vertical axis of the vehicle. In the main algorithm, the rotation rate is evaluated. Using the measured values of the acceleration sensors, one may, on the one hand, recognize the kind of turnover, and, on the other hand, these values may be used for plausibility checks. If the rotation rate algorithm detects a turnover, safety measures are activated only by simultaneous release by the plausibility control.
An additional method for determining a rollover procedure, based on two linear acceleration sensors, may be seen in patent documents German Patent No. 196 51 124 and German Patent No. 199 62 687. An additional example for illustration is seen in German Published Patent Application No. 197 44 083, in which two independent decision criteria must be present in order for the signals from one rotation rate measuring device and two acceleration sensors lead to a triggering of a safety device.
In all patents and applications it is the aim to activate a triggering of restraint systems or safety systems, in response to a rollover procedure. Other applications are not known.